Glucose Challenge Test Results Research Articles

943 Abnormal glucose screening in an index pregnancy and gestational diabetes in a subsequent pregnancy

In a non-diabetic pregnancy, the current practice is universal screening for gestational diabetes (GDM) using a 1-hour glucose challenge test (GCT) regardless of prior history. We aimed to determine whether an abnormal 1-hour GCT from an index pregnancy (PG1) can be used to guide GDM testing in a subsequent pregnancy (PG2). This was a retrospective cohort study of women who delivered 2 singleton pregnancies at >24 weeks from June 2009-December 2018 at a single institution. All patients had an abnormal PG1 GCT result (> 140 mg/dL). GDM was defined by GCT of >200mg/dL, >2 elevated values on a 3-hour diagnostic test (Carpenter-Coustan criteria), or a diagnosis by ICD codes. Univariable and multivariable analyses (MVA) were performed to examine the relationship between GDM in PG2 with variables from PG1. Given the high likelihood of GDM in subsequent pregnancies among women with GDM in PG1, the MVA was restricted to patients who were non-diabetic in PG1. 820 women met inclusion criteria, 356 (43.4%) had an abnormal 1-hour GCT in PG2, 233 (28.4%) developed GDM in PG2, and 48 (20.6%) of patients received a diagnosis of GDM without meeting laboratory criteria (Table 1). In MVA of subjects in a non-diabetic PG1, those with GDM in PG2 were significantly more likely to have higher GCTs in PG1, be of Asian race and have had gestational hypertension (gHTN) in PG1 (Table 2). In a non-diabetic PG1, the risk of GDM in PG2 increases with PG1 GCT result, Asian race and a history of gHTN. Of all patients with an abnormal PG1 GCT, regardless of PG1 diabetic status, 43.4% had an abnormal 1-hour GCT in PG2 with over a quarter of these patients diagnosed with GDM. Furthermore, our observation that 20.6% of patients diagnosed with GDM without laboratory criteria suggests that these women are considered at higher risk and are receiving the diagnosis of GDM regardless of diagnostic criteria. Thus, consideration can be given to supplant universal screening using a 1-hour GCT with direct diagnostic testing in women with a history of abnormal 1-hour screens in a prior pregnancy.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Two-day postpartum compared with 4- to 12-week postpartum glucose tolerance testing for women with gestational diabetes

A majority of women in the United States with gestational diabetes mellitus do not undergo the recommended 4- to 12-week postpartum glucose tolerance test. This study aimed to compare the diagnostic value of the 2-day postpartum glucose tolerance test with the 4- to 12-week postpartum glucose tolerance test to identify impaired glucose metabolism at 1 year after delivery among women with gestational diabetes. Postpartum women who delivered at 1 hospital between January 2017 and July 2018 were offered enrollment in a prospective cohort if they had gestational diabetes mellitus diagnosed by Carpenter-Coustan criteria or a 1-hour glucose challenge test result of ≥200 mg/dL, spoke English or Spanish, and planned to remain in the hospital for at least 2 days after delivery. Participating women underwent a 75-gram 2-hour glucose tolerance test on postpartum day 2 and were incentivized to have a 4- to 12-week glucose tolerance test and measurement of glycosylated hemoglobin at 1 year after delivery. Participants and providers were blinded to the 2-day postpartum results. The diagnostic value of an abnormal 2-day postpartum glucose tolerance test (fasting result of ≥100 mg/dL or 2-hour glucose tolerance test result of ≥140 mg/dL) was compared with that of an abnormal 4- to 12-week glucose tolerance test to identify impaired glucose metabolism (≥5.7% glycosylated hemoglobin) and diabetes (≥6.5% glycosylated hemoglobin) at 1 year after delivery. Receiver operating characteristic (ROC) curves were also compared at 2 days and 4-12 weeks after delivery. Of the 300 recruited women, 296 (99%) completed the 2-day postpartum glucose tolerance test, and 202 (68%) returned for the 4- to 12-week glucose tolerance test. Approximately 1 year after delivery, 203 (68%) women had their glycosylated hemoglobin measured, of whom 35% had impaired glucose metabolism and 4% had diabetes. The study population was diverse (46% nonwhite). Furthermore, 56% were obese (mean body mass index, 32 kg/m2), and 55% had received medication to control their glucose during pregnancy. There were no significant differences between the 2-day and 4- to 12-week postpartum glucose tolerance tests in predicting impaired glucose metabolism based on ≥5.7% glycosylated hemoglobin in 1 year after delivery: sensitivity (46% vs 36%); specificity (79% vs 84%); positive predictive value (52% vs 53%); and negative predictive value (75% vs 72%). There was also no difference between the 2-day and the 4- to 12-week glucose tolerance tests in identifying diabetes at 1 year after delivery. Both the 2-day and 4- to 12-week glucose tolerance tests had similar ROC curves in identifying impaired glucose metabolism and diabetes at 1 year after delivery. Two-day postpartum glucose tolerance tests have similar diagnostic value as 4- to 12-week postpartum glucose tolerance tests in predicting impaired glucose metabolism and diabetes at 1 year after delivery and are associated with nearly 100% adherence to the test. Thus, changing the timing of the glucose tolerance test should be considered.

Association between false positive glucose challenge test results and large-for-gestational-age infants: a retrospective cohort study

ObjectivesThere is no consensus regarding a possible relation between false positive glucose challenge test (GCT) results and large-for-gestational-age (LGA) infants. This study aimed to clarify the association between false positive...

Markers for undiagnosed type 2 diabetes mellitus during pregnancy-A population-based retrospective cohort study.

To examine possible markers for undiagnosed type 2 diabetes in early-onset gestational diabetes mellitus (GDM). A population-based retrospective cohort study of women with GDM diagnosed prior to the 24th week, who delivered between 2005 and 2018, was conducted. The results of the 50-g glucose challenge test, 100-g oral glucose tolerance test, and the first available glycosylated hemoglobin (HbA1c) were examined as markers for type 2 diabetes diagnosed 6 to 12 weeks post pregnancy, which is suggestive of pregestational diabetes. This was done by calculating the area under the curve (AUC) of the receiver operating characteristic (ROC) curve for each marker. These markers and additional ones were evaluated for independency by stepwise multivariate logistic regression. Of 69 417 pregnancies, 3321 (5%) pregnancies were with GDM. Of them, in 261 (8%) women GDM was diagnosed prior to the 24th week, and 219 (84%) women had available data for analysis. Among them, 11 (5%) women had type 2 diabetes post pregnancy. Elevated HbA1c was the most accurate marker for undiagnosed type 2 diabetes (AUC 91% with 95% CI [81%-100%]) and the only independent marker for undiagnosed type 2 diabetes in multivariate analysis (odds ratio [OR] 19; 95% CI [3.2-109], C statistic = 88%). Using the ROC curve, a cutoff of 5.8% predicted type 2 diabetes with 89% sensitivity, 86% specificity, 99.4% negative predictive value, and 23% positive predictive value. Early-onset GDM with HbA1c ≥ 5.8% should be managed as type 2 diabetes. Definitive diagnosis should be done after delivery.

Pregnant Women Become Sweeter: A Population-Based Study of Trends in Glucose Challenge Test Results Over a Decade.

Background: Glucose challenge tests (GCTs) are widely used to screen for gestational diabetes mellitus. Women with high normal GCT results may be at increased risk for immediate obstetric complications and future diabetes. We analyzed the ∼10-year trend in mean GCT results and incidence of high normal (125-140 mg/dL) and abnormal GCT results (>140 mg/dL) in a large cohort of women in Israel. Materials and Methods: Data on all GCTs performed between 2005 and 2016 were gathered from the computerized database of the Central District of Clalit Health Services, the largest Health Maintenance Organization in Israel. Trends over time were studied by time series analysis, and a multivariable logistic model was constructed to study the risk for abnormal results, while adjusting for maternal age and body mass index (BMI). Results: Altogether 101,359 GCTs were analyzed. Over the study period, mean maternal age increased from 28.7 ± 5.1 to 30.1 ± 5.1 years and mean GCT results from 101.7 to 114.6 mg/dL (p < 0.001, for both), whereas the incidence of women with abnormal GCT (>140 mg/dL) increased from 10.6% to 18.1% (p < 0.001) and of those with high normal GCT (>125 mg/dL) from 20.2% to 31.3% (p < 0.001). A multivariable logistic model revealed that later years were associated with an increased risk for abnormal GCT result, while adjusting for maternal age and BMI (adjusted odds ratio = 1.07; 95% confidence interval 1.07-1.08). Conclusions: Over ∼10 years, mean GCT results and high GCT incidence have significantly increased. These findings are in line with the worldwide diabetes epidemic and demonstrate the worsening in glucose metabolism also in relatively young women.

Glucose screening in pregnancy and future risk of cardiovascular disease in women: a retrospective, population-based cohort study

In studies to date, gestational diabetes has consistently been associated with an increased future risk of cardiovascular disease, irrespective of the antepartum screening protocol or diagnostic criteria by which gestational diabetes is diagnosed. We reasoned that the resultant heterogeneity in the severity of dysglycaemia in women with gestational diabetes suggests that the relationship between gestational glycaemia and subsequent cardiovascular disease probably extends into the non-diagnostic range. Thus, we hypothesised that glucose screening in pregnancy would identify future risk of cardiovascular disease in women who did not have gestational diabetes. We did a population-based cohort study using information from health-care administrative databases from the Ministry of Health and Long Term Care of Ontario (Canada). We identified all women in Ontario who had a 50 g oral glucose challenge test in pregnancy between 24 and 28 weeks gestation with a livebirth delivery between July 1, 2007, and Dec 31, 2015. Women who had a history of diabetes before pregnancy or had been previously hospitalised for cardiovascular disease were excluded. Women with a 1-h post-challenge plasma glucose concentration of 11·1 mmol/L or greater were considered to have gestational diabetes, as were women with a reading between 7·8 and 11·0 mmol/L inclusive for whom diabetes was recorded as a diagnosis on the delivery hospital record. The study population was divided into six groups based on the results of the glucose challenge test (≤4·8 mmol/L; 4·9-5·5 mmol/L; 5·6-6·2 mmol/L; 6·3-6·9 mmol/L; 7·0-7·9 mmol/L; and ≥8·0 mmol/L). The primary outcome was cardiovascular disease (a composite of hospitalisation for myocardial infarction, acute coronary syndrome, stroke, coronary artery bypass grafting, percutaneous coronary intervention, or carotid endarterectomy). All women were followed up from the index pregnancy until cardiovascular disease event, death, migration, or Sept 30, 2017, whichever came first. 259 164 women were identified as eligible for this study: 13 609 who had gestational diabetes, and 245 555 women without gestational diabetes. The women were followed up over a median 3·9 years (IQR 2·8-5·6) for the development of cardiovascular disease. Each 1 mmol/L increment in the glucose challenge test result was associated with a 13% higher risk of cardiovascular disease (after adjustment for age, ethnicity, income, and rurality, adjusted hazard ratio [HR] 1·13, 95% CI 1·04-1·22). This relationship persisted after excluding women with gestational diabetes (1·14, 1·01-1·28). In women without gestational diabetes, those with an abnormal glucose challenge test result (≥7·8 mmol/L) and those with a result between 7·2 and 7·7 mmol/L had an increased risk of cardiovascular disease (HR 1·94, 95% CI 1·29-2·92; and 1·65, 0·99-2·76, respectively), compared with those with a result of 7·1 mmol/L or less (overall p=0·003). The relationship between gestational glycaemia and subsequent risk of cardiovascular disease extends into the normoglycaemic range. Accordingly, glucose screening in pregnancy could identify future risk of cardiovascular disease in women who do not have gestational diabetes. None.

Relationship of Maternal Weight Status Before, During, and After Pregnancy with Breast Milk Hormone Concentrations.

The aim of this study was to test associations of prepregnancy BMI, gestational weight gain, oral glucose challenge test results, and postpartum weight loss as predictors of breast milk leptin, insulin, and adiponectin concentrations and whether these relationships vary over time. Milk was collected at 1 and 3months from 135 exclusively breastfeeding women from the longitudinal Mothers and Infants Linked for Healthy Growth (MILk) study. Hormones were assayed in skimmed samples using ELISA. Mixed-effects linear regression models were employed to assess main effects and effect-by-time interactions on hormone concentrations. In adjusted models, BMI was positively associated with milk leptin (P<0.001) and insulin (P=0.03) and negatively associated with milk adiponectin (P=0.02); however, the association was stronger with insulin and weaker with adiponectin at 3months than at 1month (time interaction P=0.017 for insulin and P=0.045 for adiponectin). Gestational weight gain was positively associated and postpartum weight loss was negatively associated with milk leptin (both P<0.001), independent of BMI. Oral glucose challenge test results were not associated with these milk hormone concentrations. Maternal weight status before, during, and after pregnancy contributes to interindividual variation in human milk composition. Continuing work will assess the role of these and other milk bioactive factors in altering infant metabolic outcomes.

403: Screening for GDM– can we use the results of the GCT of the previous pregnancy?

To assess whether previous pregnancy glucose challenge test (GCT) result among non-diabetic women may serve in an index pregnancy. as a screening tool for Gestational Diabetes Mellitus (GDM) Retrospective study based on computerized records in a single large university medical center. All women who had a singleton pregnancy and two subsequent deliveries in our medical center between 2005 and 2017 were included. Women with Diabetes Mellitus or GDM in the previous pregnancy and women without documented GCT results in their previous pregnancy, were excluded. GDM diagnosis is based on either National Diabetes Data Group criteria or the Carpenter and Coustan criteria. Unpaired student T-test and one way ANOVA were used to asses associations between GCT levels and maternal characteristics. Multivariable logistic model was conducted to assess the independent role of GCT level at previous pregnancy on GDM at index pregnancy. ROC curves were constructed. All tests are two-sided. P value below 0.05 was considered statistically significant. Analyses were carried out using SPSS software package version 22 (IBM, Armonk, NY). A total of 31,861 women met inclusion criteria. Of those, 670 (2.1%) had GDM in the index pregnancy. Parturients with GDM in the index pregnancy had higher mean levels of GCT in the previous pregnancy in comparison to parturients without GDM (127.5±28 VS. 98.7±24 mg/dl, respectively, p<0.001). There was a positive association between GCT results in previous pregnancy and rates of GDM in index pregnancy (Figure). Multivariate analysis controlling for known risk factors for GDM revealed that GCT levels in previous pregnancy were independently associated with rates of GDM in index pregnancy (1.04, 95% CI 1.03-1.04, p<0.001). Using a GCT value of 107 mg/dl (65th percentile), the area under the ROC curve was 0.79, suggesting a fair to good accuracy of GCT results in previous pregnancy in predicting GDM in index pregnancy. In addition, the NPV of this value is very high, only 7 of 1000 women with this results or lower will have GDM in the index pregnancy (Table). GCT result in previous pregnancy may serve as a screening tool for GDM in an index pregnancy. Parturients with low levels of GCT may not need repeat screening for GDM in the index pregnancy.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

414: High-normal 50-gram glucose challenge test and future metabolic diseases: a population- based study

A 1-hour 50-gram glucose challenge test (GCT) is the first step in the screening for gestational diabetes mellitus (GDM). Accumulating evidence show that women with high- normal GCT levels are at elevated risk for immediate obstetric complications such as large for gestational age newborns and greater likelihood for caesarean delivery. We sought to examine the risk for metabolic disorders later in life, among women with high-normal GCT levels, as compared to low normal and abnormal GCT. This cohort study included all pregnant women who underwent GCT between the years 2005 to 2018 at the Central District of Clalit Health Services, the largest health maintenance organization in Israel. Rates of metabolic diseases (MTD) were compared between the three study groups: women with history of only Low-normal GCT (<124 mg/dL), High normal (125- 139 mg/dL) and abnormal GCT >140 mg/dL. Data on maternal ages and GCT results for each test performed, as well as MTD such as diabetes and obesity were collected and analyzed from the computerized database. Multivariable survival model was used to study the association between GCT levels and MTD risk, while adjusting for maternal age. A total of 66,869 women performed 1 to 10 GCTs to a total of 117,435 tests during the study period; 23% of study participants (n=15,360) had at least one abnormal result; 11.3% (n=7566) of participants had a diagnosis of MTD. As compared to women with low normal GCT (only), women with a history of high normal and abnormal GCT were at higher risk for MTD (10.4% vs. 12.4% and 13.0%, p<0.001, age adjusted HR=1.18; 95%CI 1.09-1.24, and 1.18; 95%CI 1.11-1.25, for high normal and abnormal GCT, respectively). There was no significant difference in MTD risk between women with history of high normal and abnormal GCT results (age adjusted HR=1.02; 95%CI 0.94-1.10; p=0.67). As compared to women with low normal GCT, women with high normal GCT, similarly to women with abnormal GCT, are at increased MTD risk. Although GCT is a screening test, it may be a predictor of MTD later in life, and women with high normal GCT results may benefit from close monitoring of their metabolic status.

Pregnant women may be sweeter in the summer: Seasonal changes in glucose challenge tests results. A population-based study

AimsA 1-hour, 50-gram glucose challenge test (GCT) is the first step in the diagnosis of gestational diabetes mellitus (GDM). Seasonal fluctuations in fasting glucose levels and GCT results were previously described. We sought to investigate seasonal changes in GCT results in a large cohort. MethodsGCT results were analyzed of all women insured at the Central District of Clalit Health Services (the largest health maintenance organization in Israel), between the years 2005 and 2016. ResultsA total of 101,359 GCT results were analyzed. Mean GCT was 110 ± 28.9 mg/dL, and 14.5% (n = 14,652) were pathological. Both the mean and the incidence of pathological GCT were lowest in the winter, followed by spring, fall, and summer, (p for trend < 0.001). The difference in mean GCT between winter and summer was 7.82 ± 0.24 mg/dL (95% CI, 7.35–8.29). After adjustment for BMI and age, having a GCT in the winter was independently associated with the lowest risk for pathological GCT, as compared to all other seasons. ConclusionsSeasonal changes in GCT results should be studied further in additional regions, and if found, the cutoff threshold for abnormal GCT should be re-examined and adapted to local weather conditions and seasonal variability.

Relationship between 50-g glucose challenge test and large for gestational age infants among pregnant women without gestational diabetes

The study aimed to compare the incidence of large for gestational age (LGA) infants between women with a false positive and normal glucose challenge test (GCT), and to evaluate the factors associated with LGA. A total of 480 pregnant women at risk for gestational diabetes mellitus (GDM); 160 with a false positive GCT and 320 with normal GCT results were included. The incidence of LGA and other pregnancy outcomes were compared between the two groups. Possible associated factors for LGA were also evaluated. Women with a false positive GCT were significantly older and more likely to be multiparous. The incidence of LGA was comparable between the false positive and normal GCT groups (15.6% vs. 13.1%, p = .456). Other pregnancy outcomes were also comparable. Logistic regression analysis showed that pre-pregnancy underweight significantly reduced the risk of LGA (adjusted OR 0.25, 95% CI 0.07–0.87, p = .029) while a second trimester weight gain >7 kg significantly increased the risk of LGA (adjusted OR 3.13, 95% CI 1.67–5.89, p < .001).Impact StatementWhat is already known on this subject? Women with a false-positive GCT (abnormal GCT but normal OGTT) can be considered as having an early form of glucose intolerance which similar adverse outcomes to GDM could develop. Previous studies have reported that a mild maternal hyperglycaemia in the absence of GDM is associated with LGA, macrosomia, shoulder dystocia and a caesarean delivery. There is no current recommendation for any intervention or treatment among women with a false positive GCT.What the results of this study add? The results of this study showed that an incidence of LGA was not significantly increased in the false positive GCT groups and that other pregnancy outcomes were comparable. A pre-pregnancy underweight significantly reduced the risk of LGA while a second trimester weight gain >7 kg significantly increased the risk of LGA.What the implications are of these findings for clinical practice and/or further research? As a gestational weight gain is modifiable, behavioural and a dietary intervention as well as a close monitoring of the weight gain could help in lowering the risk of LGA, even in the absence of GDM. Further studies which are more widely generalisable are needed to elucidate the relationship between 50 g GCT and the adverse outcomes and to investigate the benefits of a specific intervention among this specific group of women.

Short Body Height and Pre-pregnancy Overweight for Increased Risk of Gestational Diabetes Mellitus: A Population-Based Cohort Study.

Background: Short height is associated with gestational diabetes mellitus (GDM) but the underlying mechanism remains unknown. This study aims to explore whether short height has a synergistic effect with pre-pregnancy overweight/obesity and undue weight gain on the risk of GDM.Methods: We recruited 19,962 singleton pregnant women from their first antenatal care visit in urban Tianjin, China, between October 2010 to August 2012. At 24–28 weeks of gestation, women underwent a 50-g 1-h glucose challenge test (GCT) followed by a 75-g 2-h oral glucose tolerance test (OGTT) if the GCT result was ≥7.8 mmol/L. GDM was defined by the International Association of Diabetes and Pregnancy Study Group's cut-points. Univariable and multivariable logistic regression analyses were performed to obtain odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic spline (RCS) analysis nested in the logistic regression analysis was used to identify a cutoff point of height for GDM. Additive interaction was used to test interactions between short height, pregnancy overweight/obesity and undue weight gain.Results: A total of 1,517 (or 7.6%) women developed GDM. The risk of GDM increased rapidly with a decreasing height from 158 cm and downwards. Using height ≥158 cm as the reference group, women with < 158 cm of height were at increased GDM risk (adjusted OR: 1.44, 95%CI: 1.18–1.75). Maternal overweight/obesity at the first antenatal care visit greatly enhanced the OR of short height for GDM (adjusted OR: 3.78, 95%CI: 2.84–5.03) with significant additive interaction (P < 0.05). However, the interaction between short height and undue weight gain was non-significant (P > 0.05).Conclusions: In Chinese pregnant women in urban Tianjin, height < 158 cm had a synergistic effect with pre-pregnancy overweight/obesity on the risk of GDM.

Enhancing the functional output of transplanted islets in diabetic mice using a drug-eluting scaffold

BackgroundIslet transplantation is increasingly used in the diabetic patients to control the blood glucose level. However, the functional output of transplanted islets remains hampered due to the local inflammation, loss of islets, etc. To that end, in this study we explored to enhance the functional output of transplanted islets in diabetic mice by employing a drug-eluting scaffold with a payload of interleukin 4 (IL-4).ResultsAccording to the in vitro studies, the scaffold showed no cytotoxicity, a rapid release of IL-4 within a week and the IL-4 retained its bioactivity. During the 4-week time window after the islet transplantation, in vivo studies showed that the levels of blood insulin and C-peptide 2 in diabetic mice in the drug-eluting scaffold group significantly increased since week 2, which effectively reduced the blood glucose level. In addition, these mice demonstrated a stronger capability to withstand a rapid glucose spike as evidenced by the tolerance of sudden oral glucose challenge test result. A further mechanistic study suggested that the enhanced functional output could be attributed to the M2 polarization of macrophages as evidenced by the increase of CD163+/CD68+ macrophages in the islet tissues. A M2 polarization of macrophages is widely believed to exert an anti-inflammatory influence on local tissues, which could accelerate the resolution of local inflammation following the islet transplantation.ConclusionOur study shed a new light on the hyperglycemia management of diabetic patients following the islet transplantation.

Incidence, risk factors, and pregnancy outcomes of gestational diabetes mellitus using one-step versus two-step diagnostic approaches: A population-based cohort study in Isfahan, Iran

AimsTo study the incidence, risk factors, and pregnancy outcomes associated with gestational diabetes mellitus (GDM) diagnosed with one-step and two-step screening approaches. Methods1000 pregnant women who were eligible and consented to participate underwent fasting plasma glucose testing at the first prenatal visit (6–14 weeks). The women free from GDM or overt diabetes were screened at 24–28 weeks using the 50-g glucose challenge test (GCT) followed by 100-g, 3-h oral glucose tolerance test (OGTT) (two-step method). Regardless of the GCT result, all women underwent a 75-g, 2-h OGTT within one-week interval (one-step method). ResultsGDM incidence using the one-step and two-step methods was 9.3% (95% CI: 7.4–11.2) and 4.2% (95% CI: 2.9–5.5). GDM significantly increased the risk of macrosomia, gestational hypertension, preeclampsia, and cesarean section and older age and family history of diabetes significantly increased the risk of developing GDM in both approaches. In two-step method, higher pre-pregnancy body mass index and lower physical activity during pregnancy along with higher earlier cesarean section also increased significantly the risk of developing GDM. ConclusionsDespite a higher incidence of GDM using the one-step approach, more risk factors for and a stronger effect of GDM on adverse pregnancy outcomes were found when using the two-step approach. Longer follow-up of women with and without GDM may change the results using both approaches.

Clinical significance of low result of 1-h 50-g glucose-challenge test in pregnant women

Objective: The objective of this study is to examine the effect of low-glucose value on the 1-h 50-g glucose challenge test (GCT) on neonatal body weight in low-risk Asian singleton pregnant women. Method: We retrospectively analyzed women who delivered a singleton neonate at term at a tertiary center and underwent GCT at 24–28 weeks of gestation between June 2001 and June 2015. The low GCT group was defined as <75 mg/dL and 75–139 mg/dL were control. We compared these two groups of maternal characteristics, small for gestational age neonate (SGA), large for gestational age neonate (LGA), low-birth weight, and macrosomia. The χ 2 test, Fisher’s exact test, and Student’s t test were used. Results: There were 313 low GCT groups and 4611 control. The low GCT group were younger, had lower prepregnancy body weight, higher stature, and lower prepregnancy body mass index (BMI). After adjusting these variables, the low GCT group had a lower rate of LGA and a higher rate of SGA. Neonatal body weight is more influenced by maternal physique than by low GCT result (standardized coefficient (β); GCT 0.071, height 0.188, prepregnancy BMI 0.143). Conclusions: Neonatal body weight was only slightly influenced by low GCT result, but markedly influenced by maternal physique, such as height and prepregnancy BMI.

850: Trends in Glucose Challenge test results: A population based study of over a decade

The incidence and prevalence of diabetes is constantly rising in the western world, partly due to the aging global population and the obesity pandemic. Gestational diabetes rates seem to be rising as well, due to similar reasons. One-hour glucose challenge test (GCT), measuring the effect of 50-grams glucose solution on blood glucose levels, is generally performed during pregnancy in young healthy women, with no previous history of impaired fasting glucose, gestational diabetes, morbid obesity, etc. We sought to analyze trends over the years in GCT results in a large population of healthy parturients. Data was gathered from a computerized database of a large Health Maintenance Organization, including all GCTs performed between 2006 and 2015. Mean GCT results were evaluated over the years and the incidence of abnormal results (>140 mg/dl). Time series analysis was performed to test the yearly trend, and a multivariable logistic model was constructed to study the risk for abnormal results over the years, while adjusting for maternal age. During the study period 92,676 GCT tests were available for analysis. Mean maternal age, mean GCT results and the incidence rates of abnormal results (>140mg/dl) all increased over the years: 28.7±5.1y in the first year (2006) to 30.1±5.1y in the last year (2015), 106±29 to 113±29 mg/dl, and 12.3% to 16.4%, with a positive trend over the years for all variables (p for trend <0.001 for all) (Graph). A multivariable logistic model revealed that later years were associated with an increased risk for abnormal GCT result, while adjusting for maternal age (Adj. OR=1.07; 95%CI 1.07-1.08). GCT is a screening test generally performed in pregnant women with no diabetic predisposition. In this large population, the mean GCT results gradually increase over a period of a decade by an average of 7 mg/dl and the incidence of abnormal GCT rises in parallel. This rise cannot be explained only by the aging population but rather by other modern western life characteristics.

Effect of borderline glucose intolerance on fetal maternal outcome

Purpose of investigation: The aim of this study was to compare the maternal and neonatal adverse outcomes in pregnant women whose glucose challenge test (GCT) results were below 130 mg/dl and between 130-139 mg/dl. Materials and Methods: Three hundred and six women with 50-gram GCT results of 130-139 mg/dl and 305 women with 50-gram GCT results of Results: Higher pre-postpartum hemoglobin difference (p = 0.001), longer postpartum hospitalisation time (p = 0.001), and increased cesarean section rates (p = 0.01) were reported in the study group. There were no differences between two groups in rates of preeclampsia, polyhydramnios, ablatio placenta, and chorioamnionitis. Conclusions: The authors suggest that a GCT result between 130-139 mg/dl is not associated with higher maternal and neonatal morbidity. Results do not support a conclusion of high maternal and neonatal morbidity in the study group and give an impression that the 140 mg/dl threshold value is adequate for screening.

Predictive Characteristics of Elevated 1-Hour Glucose Challenge Test Results for Gestational Diabetes.

Objective The objective was to estimate the optimal screen-positive 1-hour 50 g glucose challenge test (GCT) threshold for gestational diabetes (GDM) and predictive characteristics of increasing screen-positive GCT threshold values (135–199 mg/dL) for GDM. Study Design It is a secondary analysis of a multicenter mild GDM study. At 24 to 30 weeks' gestation, women with elevated GCT (135–199 mg/dL) completed a diagnostic 3-hour oral glucose tolerance test (OGTT). A novel change-point analysis method was used to compare the GDM rates for the adjacent GCT values, delineating categories of changing risk such that values within categories have equal risk for GDM. Positive (PPV) and negative (NPV) predictive values for GDM were computed for increasing GCT cut-offs. Results In 7,280 women with both GCT (135–199 mg/dL) and OGTT results, 4 GDM risk-equivalent GCT categories were identified with escalations at 144, 158, and 174 mg/dL (all p-values &lt;0.05). The PPV for GDM increased from 33 to 64% as GCT increased from 135 to 199 mg/dL, while the NPV decreased from 80 to 67%. PPVs were only 20% and 61% for risk-equivalent categories of 135 to 143 mg/dL and 174 to 199 mg/dL, respectively. Conclusion Elevated GCT cut-off values between 135 and 143 mg/dL may carry equivalent GDM risk. No threshold GCT value &lt;199 mg/dL alone sufficiently predicts GDM.

Associations of mid-pregnancy HbA1c with gestational diabetes and risk of adverse pregnancy outcomes in high-risk Taiwanese women.

BackgroundThe objective of this study was to investigate the associations among the mid-pregnancy glycated hemoglobin A1c (HbA1c) level, gestational diabetes (GDM), and risk of adverse pregnancy outcomes in women without overt diabetes and with positive 50-g, 1-h glucose challenge test (GCT) results (140 mg/dL or greater).MethodsThis prospective study enrolled 1,989 pregnant Taiwanese women. A two-step approach, including a 50-g, 1-h GCT and 100-g, 3-h oral glucose tolerance test (OGTT), was employed for the diagnosis of GDM at weeks 23–32. The mid-pregnancy HbA1c level was measured at the time the OGTT was performed. A receiver operating characteristic (ROC) curve was used to determine the relationship between the mid-pregnancy HbA1c level and GDM. Multiple logistic regression models were implemented to assess the relationships between the mid-pregnancy HbA1c level and adverse pregnancy outcomes.ResultsAn ROC curve demonstrated that the optimal mid-pregnancy HbA1c cut-off point to predict GDM, as diagnosed by the Carpenter-Coustan criteria using a two-step approach, was 5.7%. The area under the ROC curve of the mid-pregnancy HbA1c level for GDM was 0.70. Compared with the levels of 4.5–4.9%, higher mid-pregnancy HbA1c levels (5.0–5.4, 5.5–5.9, 6.0–6.4, 6.5–6.9, and >7.0%) were significantly associated with increased risks of gestational hypertension or preeclampsia, preterm delivery, admission to the neonatal intensive care unit, low birth weight, and macrosomia (the odds ratio [OR] ranges were 1.20–9.98, 1.31–5.16, 0.88–3.15, 0.89–4.10, and 2.22–27.86, respectively).ConclusionsThe mid-pregnancy HbA1c level was associated with various adverse pregnancy outcomes in high-risk Taiwanese women. However, it lacked adequate sensitivity and specificity to replace the two-step approach in the diagnosis of GDM. The current study comprised a single-center prospective study; thus, additional, randomized control design studies are required.

Predictive Characteristics of Elevated 1-Hour Glucose Challenge Test Results for Gestational Diabetes

Predictive Characteristics of Elevated 1-Hour Glucose Challenge Test Results for Gestational Diabetes